Flying-machine



P. C. HEWITT. FLYING MACHINE, APPLx'cAmN FILED 11111214, 1919.

Patented May 17,1921.

2 SHEETS-SHEET l.

www( JAJATTORN Ys P. C. HEWITI". n

FLYING MACHINE.. APPLICATION FILED JUNE E4, 1919.

UNITED s Ty.1.TE s PATENT OFFICE.

PETER cooPERHEWITT, or RINGWooD MANOR, NEW JERSEY.

. 'Y FLYINGrMACHINE.

To all whom t may concern: Y v

Be it'known that I, PETERCOOPER Hnwrrr, a citizen of the United States, and a resident of Ringwood Manor,"in the county of Passaic and State of New Jersey, have invented certain Vnew and useful Improvements in F1ying-l\.lachines, of which the Afollowing is a specification.

My invention relates to flying machines and more particularly to flying machines vof the typeV known as helicopters in which the machine is lifted 'by the action of one or more propellers rotating about a' vertical or upright axis.

The general object of the invention to provide an improved machine of this type; but many of the features are not limited to such machines. j

Another object of the vinvention iisvto provide an efficient helicopter of compact and strong construction and of light weight." YAnother object -of the invention is to provide an improved propeller construction, suitable for a helicopter, in which blades of any desired improvedk form, even if very thin, may be used without sacrificing the strength of the propeller for the eliiciency of the blades. l y

Other objects, features and advantages of my' invention will appear more fully in the` following detailed description and theapw pended claims.

The accompanying drawings forming part of this specification illustrate one embodiment of my invention.

In the drawings; Figure lis al side elevation ofsaid embodiment of my invention, part ofthe fuselage being broken away. Y 2 is atop plan view thereof.

Fi U.

of atportion of the landing device.

Fig. 5 is a detaily portion of the landing device.

F ig. 6 is a detail planview, on a scaleof one of the propeller f larger than Figll,

arms.

Fig; 7 isv a'verticalV sectional v view takenV of an end portion of one of the wires used in theconstruction shown.v

normally vertical shaft .3

'beveled pinion 11.

ig. Bis a section taken on line Sw?) of e. l

Fie. 4 is an end view on an enlarged scale plan view of another lSpecification of Letters Patent. Patgnted lvIay 17,' 1921. Ap'pnetn anemie 14, 1919. serial No. `304,192.

The helicopter shown comprises an upper propeller 1 and 'a propeller 2 .below the same, the propeller 1 being carried by a which passes ghrough the tubular shaft 4 of the propeller tubular bearing 5 forming part of the frame G of the machine, and stationary with respect thereto. This frame carries a fuselage 7.

The shafts l3 and 4 and the propellers carried thereby are driven in opposite directions by motorsor engines 8 and 9 of equal power arranged one to the front andthe other to the rear of the shafts 3 and 4, and

having their driving shafts arranged in axial alinement longitudinally of the fuselage 7, the axis of said driving shafts intersecting the axis of the shafts 3 'and 4. at right angles. The shaft of the engine or lmotor Sis provided with a beveled pinion 10, and the shaft of the motor 9 with the Each of these pinions meshes with a beveled gear 12 secured to the shaft 4 above the pinion, and also with the beveled gear 14 secured to the shaft 3 below the pinion.

The arrangement shown is such that a balanced action is obtained in driving the shafts 3 and 4, and there is substantially no lateral thrust on the various bearings inasmuch as each moving'part of the mechanism is acted upon by equal yforces acting in opposite directions. Each of the gears 12 and 14, for example, is acted upon on one side wardly, referring to Fig.. 1, while on the I other side of its axis it is acted upon by the pinion 11, tending to drive the same with equal force in the opposite direction, or

rearwardly in the case assumed. In otherV words, a true dynamic couple is obtained,`

causing rotation with little or no lateral thrust upon the bearings, with the motors exercising equal power. The'driving means for the' propellers are claimed in another application filed on even date herewith, and a further description thereof'is thought to be unnecessary herein.

-Each of lthe propellers, as shown, comprises two blades 16 and 17 arranged on opposite sides of the axisof the propeller shafts 3 and 4. Theblades of each propeller are supported by a rigid truss secured Y however, desirably terminate at their imier midway between its ends to the correspond` ing propeller shaft. Each of the trusses, as shown, comprises asubstantially horizontal compression member 19 extending radially Afrom the propeller shaft and a compression `Vmember 2O extending from the corresponding ends a distance from the'aXis of the `ro Del# ler at Vleast one-fifth the radius off the propeller and preferably a greater distance.

The struts 21 are arranged at gradually diminishing distances apart `from the axis of the propellers to the outer ends of the propeller arms and the compression members-2O are inclined so as to approach the members 19 andthe propeller blades gradually more closely toward the outer ends ofV saidarms. As shown in Fig. 2, the struts 21 and the compression members 20 are consecutively of dimimshmg cross section from the inner toward the outer ends of the propeller arms. The construction is,'therefore, such that the trusses have the greatest strength at their inner ends where the total loadthereonis greatest.

The truss structure lor supporting means for each blade projects. from the blaue along only one of the facesthereof; and, as shown,

' the whole truss construction is arranged in peller.

the space below the-blades of the'upper propeller and above the blades of the lower prof ByA reason of this constructionvthe length of the propeller shafts between the upper end of the upper propeller and the lower endV of the4 lower 'propellermay be made relatively short with the result that theweightof the propeller shafts may be made correspondinglyv small and the machine correspondingly light and compact.

The fuselage may, with this construction, be brought up close to the lower propeller blades; .and asa result, tilting of the machine for horizontaler lateral flight may be n very easily accomplished.

Referring to Fig.`3,it will be seen 'that the propeller blades have in cross section` the shape of an aeroform aeroplane wing. Such wings have been thesubject of considerable study and many of c the improved wing shapes, known in the art as aeroform shapes,

or aerofoils, are shown vand discussed inV v arious publications including the authoritative book byEiffel entitled: The Resistance -of the Air and Aviation. Such shapes have upper and lower surfaces (or forward and rear surfaces considering the direction of thrust on the shape) of diderent contour in cross section31and it has been found that the lifting eflect on the upper surface is greater than that on the lower surfare. T he wing shape shown is shape No. 32 in said book.

By reason of the construction shown, very thin blades may be employed, inasmuch as it is not necessary'to construct the blades so that they have suflicient strength within themselves to enable them to support them selves in proper' relation to the propeller shaft, the truss affording a structure exterversely to its length is forwardly of the center of pressure upon the blade. The location of the centerfof pressure of lift depends upon various factors, including the shape of the blade and the pitch angle or angle of incidence thereof, and may be a substantial distance forwardly of the center of the blade. For a blade of the shape shown and supported as shown, the center of pressure will be between the longitudinal center Y line' of the blade and the axes of the struts 21, and closer to the latter than to the fermer. ln other words, the center of support transversely of the blade is forwardly of the center of pressure or lift and desirably not more than about' 30%'of the width of tl e blade rearwardly from the front odge thereof. As. a result, the bladeris pulled around by the supporting arm instead of being pushed, danger of chattering is obviated. The mounting of thepropeller blades so as to accomplish these results is claimed broadly in another application filed on even date herewith.

rThe various .parts ofl the truss passing through the air and encounteringV air resistance, other than the wings or blades 16, 17, are of stream line shape. rlhis includes the members 19, 20, as clearlyV shown in Fig. 8, as well as the struts 21, as shown in Fig. 6, and desirably also the wires or teni sion members 22, 23. The truss construction a horizontal direction. The use of :truss members having a stream line shape tends to strengthen the trusses against such bending.

In Figs to 9 inclusive I haveshown i means whereby the various truss members together by meansof brackets 25, which are each provided'with 'a strip A26 extending longitudinally of the truss and desirably seated' at opposite ends within adjacent sections of the member 19 so that the upper surface of said strip will lie flush with the upper surface of said member, as clearly shown in Fig. 8. The body portions of members 19 and 20 and thestruts 21 are, as shown, made of wood and the brackets 25 of a light metal, such as aluminum. Each bracket 25 is secured to adjacent ends of the wooden sections of the member 19 by means such as rivets 27, which pass through the strips 26, the wooden sections of members 19 and strips28 ofV metal, such as aluminum, fitting within thel lower portions ofv said sections of the member '19 iiush therewith. The upper ends of the wires 22, 23, are secured within tubular projections 29, 30, of the brackets 25 by means which will be more fully described hereinafter. Each bracket 25 is secured, as bya rivet 31, to the upper end of s the strut 21, the lower end of the strut being secured to a bracket 32, which is pro1 vided with strip-like extensions 33, 34. These extensions are secured, as by rivets 35, to the member 2O kofthe truss. The rivets 35, as shown, pass through projections33, 34, the wooden body portions 36 of member 20. and a strip 37 `of metal, such as aluminum, extending Vlongitudinally of the said member and having its lower surface flush with the member 20 and desirably curved in accordance v`with the stream line shape of the saidmember. lAs shown in Fig. 7, the plate 37 and the bracket 32, both of which are desirably made of light metal, such as aluminum, are'directly connected by a screw 38. The lower ends of adjacent wires 22, 23, are connected' withthe` brackets 32, as will be hereinafter more fully described.

In av propeller such as that shown the stressupon the wires 22,` 23, is very great andthis is especially true `with large propellersfor lifting' heavy' lloads. 4 The wires or tensionmembers-22, 23,' are accordingly made of avery strong material such. as steel. If these wireswere threaded directly into the brackets`25and 32 the 'loads or stresses transmitted through the threads would .be very largeand greater than practical where the brackets V25 and 32 are'made of material,`

such as` aluminum, which has insuiiicient strength'for taking such a strain, itlbeing understood that the wires 22, 23 lare of relatively small cross-sectional area and the threads thereof relatively shallow. I obviate this objection by the provision of a threaded connection whereby the wires mayy be connected to thebrackets without applying to the threads of the latter an excessive stress-per unit of area.

To the above end, the upper ends of the wires, as shown, are threaded respectively Y into nuts or sleeves '40. These nuts have peripherics which are threaded into the projections 29 or 30 of the brackets 25, the nuts 40 being desirably made of a strong metal, such as steel. The intermeshing threads of the wires and the nuts being made of strong material are able to stand, without deformation,rthe loads or stresses thereon. AThe threaded area between the nuts or sleeves and the brackets is of considerably larger diameter than, and of approximately the same length, asthe threaded area between the wires and the nuts or sleeves; so that the total threaded area between the nuts or sleeves and the brackets is very much larger than the total threaded area between the nuts or sleeves and the wires. Accordingly, the stress per unit area over the former area is smaller than the stress per unit area over the latter area. Satisfactory results may be obtained with the parts substantially in the proportion'shown for the particular construction herein described, the outer diameter of the nut being approximately three times the inner diameter thereof. The nuts as shown are provided with openings 41 by which they may be rotated by means of a suitable tool.

I find that best results are obtained by the use of a thread substantially of the shape shown in Fig. 9 in which the weak outer ends of the usual V thread, as well as the' sharp inner ends of the spaces between such threads are omitted, the sides of the thread being, however, inclined as with such V threads. `With this construction not only are theweak portions of the threads omitted, but at the same time the threads ar not cut'so deep into the wire as to unneces-v sarily reduce the strength thereof. This construction, accordingly, retains the most effective portions of the threads with the minimum weakening of the wire.

The lower ends of the wires, as shown, have'meunted thereon disks 42, the periph-v eries of which arefthreaded into the bracket 32. The disks 42 are freely rotatable aboutV or other damageto either wire or disks; and

the disks 42, which are made of strongv metal, such as steel, have a vperiphery of` a diameter materially larger than that ofthe adjacent end'of the wire. diameter .and thickness of the disks 42 of suitable size the stress per unit area between the disks and the brackets 32 may be broughtwithin practical working limits. By reason of the factthat the disks 42 are rotatable on l the wires 22, 23, they may be threaded into within the compression members of the truss and do not oder objectionable resistance to the rotation of the propellei's.

The landing device shown herein is in the nature of a staiidaifording a base of consid-y erable size by which the machine may be supported in upright position. The device, as shown, comprises a plurality of legs pivotally supported from the frame of the machine and arranged to be positioned below the fuselage for supporting machine or to be folded into close proximity to each other and lifted into operative position where they offer no objectionable resistance to the move- Vmen-t of the machine. ln the drawings three legs are shown, a forward leg 50 and two rearlegs 51 and 52 respectively. rlfhe Vleg 50 is mountedto swing about its axis 53 in a vertical plane while the legs 51, and 52, as clearly shown in Fig. 4l, are arranged to swing without their axes 511 and 55 respectively, in planes inclined downwardly and outwardly with respect to the plane in which the leg 50 moves. As shown in Figs. 1 and e, the pivot of the leg 50 is arranged below the pivots of the legs 51 and 52 so that when the legs are moved upwardly to inoperative position, as shown in dot and dash lines in Fig. 1, the leg 50 may be arranged below the legs 451 and 52. 'lt will be seen that when the legs 51 and 52 are arranged in inoperative position, as shown in dot and dash line in Fig. 1, their longitudinal axes will be Vparallel with each other and with the longitudinal axis of the leg 50 yso that.

*Ab n b u a c the legs will lie in very `close relationship with each other; whereas when the legs are lowered to operative position, as shown by solid line in Fin: 1, the legs 51 and 52, as

well the leg o0, will. have been' inclined ldownwardly and away from each other so Jthat their lower ends will be a substantial distance apart. The legs 50, 51, 52, accord-v By making theA For limiting the movement of the lower ends of legs 50, 51,52, away from each other braces 56, 57 and 58 are provided, the brace 56 being pivoted at its outer end to the leg 50 adjacent to the lower end of the latter and the braces 57 and 58 being pivoted at their outer ends to the legs 51 and 52 respectively by pinand slot connection 59, shown in Fig. 1. The inner ends of the brace members 56, 57 and 58 are connected with each other, as by a universal joint 60, as shown in plan in Fig. 5, the pin and slot connection 59 permitting collapsing of the tripod to the position shown in dotted line in Fig. 1, while permitting the location of the pivots 54 andA 55 at ay hi 'her level than the pivot 53.

ior collapsing the toggle formed by the brace members 56, 57, 58, so that the legs may be moved downwardly toward each other to the position shown in dotted lines in Fig. l, a wire or cable 61 is connected, as shown, to the member 60, this wire eX- tending over a guide roll 62 to suitableV means, such as the drum 63 for winding up or letting out the said wire. Suitable means are also provided for drawing the legs upwardly to inoperative position after lthey liave'been'collapsed to the position shown in dotted lines in Fig. 1. These means, as shown, comprise a wire or cable 65 connected to the leg 50 and extending over a guide roll 66 in the bottom of the fuselage to winding mechanism, such as the drum 67. The leg 50 may be provided with suitable means such as projections 68 on opposite sides thereof-.for engaging the legs 51 and 52 to l tive position the drum 72 is rotated to re-` lease the wire or cable 70, whereupon the drum 63 is rotated to wind up the wire or cable 62 to break the toggle 56, 57, 58, and permit the legs to move downwardly by gravity to the positionshown in the dotted linesinFig. 1. The drum 67 is then rotated to wind up the .Wire or cable 65 and move the legs into inoperative position, as shown in dotted and dash lines in Fig. 1. The fuselage may be provided with an opening or recess inv the bottom to receive the landing device, or the major portion of the latter, as shown, when the landing device is moved to inoperative position. Each Vof the drums is, of course, provided with suitable retaining mechanism which maybe of Yan desired and well known construction.

en it is desired to move the landing device to operative position, the drum 67 is rotated to release Vthe. wire or cable 65, whereupon the legs drop to the dotted position shown in Fig. 1. Upon the rotation 'in connection with the helicopter shown,

, siich, for example, as the steering means shown iii my co-pending application, Serial No.. 304,190, filed by me on even date here-v with; A description of such meansY is thought .to be unnecessary for a clear understanding of the invention and is accordingly omitted for simplicity and clearness.v

It is to be understood that many of the features'of this invention, although shown in connection with af helicopter,` are not limited to such a machine. It is also to be understood that while I have shown one em- 1 bodiment of my invention I am not limited spaced apart along said axis and comprising4 blades andmembers supporting said blades and arranged entirely within the space between the blades lof the respective pro-Y pellers.

2. The combination of two propellers and means for supporting the same for rotation about a common axis, said propellers being spaced apart along said axis and comprising blades and truss members supporting said blades and arranged entirely within the space between the blades of the respective propellers.

3. The combination of two propellers, means for supporting the same for rotation about a common axis, said propellers lbeing spaced apart along said axis and comprising blades and truss memberssupporting said blades and arranged entirely within the space between the blades of the respective propellers,vand driving means for said propellers arranged outside of said space.

4. The combination of two propellers,`

`means vfor supporting the same for rotation about a common axis, said'propellers being thereof.

spaced apart along said axis and comprising blades and truss members supporting said blades and arranged entirely within the space between the blades of the respective propellers, said members co-acting with said blades for supporting the saine against stress in opposite directions longitudinally of the axis of rotation of the propellers, and also against distortion about the axis of the propellers, and driving means for said propellers arranged outside of said space.

5. The combination of a propeller blade ofY aeroform shape and means co-acting therewith entirely along one face thereof and forming a rigid truss to support the blade, compression members of the truss having cross-sections of stream line shape.

6. A propeller having a truss of which the propeller blade forms a. part, for supporting the blade against stress in opposite directions longitudinally of the axis of rotation of propeller, the center of support of the blade being forwardly of the center of pressure thereof.

7. A propeller having a blade and truss members on one face of the blade for supporting the saine againstl stress in opposite directions longitudinally of the axis of rotation of propeller, the blade being of aeroform shape, the other exposed parts of the propeller of relatively large cross sections Vbeing of stream line shape.

8.` A propeller having a blade and supporting means for the blade arranged exteriorly thereof, the center of support of the blade being forwardly of the center of pressure thereof.

9. A propeller having a blade of aeroform shape and supporting means for the blade arranged exteriorly thereof and along one face thereof, the center of support of the blade being forwardly of the center of pressure thereof. Y

10. A propeller having a blade and supporting means for the bladeV arranged exteriorly thereof and along one face only thereof, the center of support of the blade being forwardly of the center of pressure 11. A propeller having supporting means for `the propeller blade comprising a rigid truss arranged exteriorly of the blade, the center of support of the blade being forwardly of the center of pressure.

12. The combination of two propellers and means for supporting the same for rotation about a common axis, said propellers beingY spaced apart along said axis and comprising blades and truss members supporting said blades and arranged entirely within the space between the blades ofthe respective propellers, the center ofrsupport of each blade being forwardly of thecenter of pressure thereof.

13. The combination of two propellers and means for supporting the same for rotation about a common axis, said propellers being` spaced apart along said axis and comprising 5 blades and members supporting said blades and arranged entirely within the space between the blades of the' respective pro pellers, the center of support of each blade being forwardly of the Center of pressure thereof. 1 lo In testimony whereof I have signed my name to this specification. Y

PETER ooornnnnwrrr. 

